US2824355A

US2824355A - Device for setting up molds for the construction of concrete steps

Info

Publication number: US2824355A
Application number: US557915A
Authority: US
Inventors: Guy W Griset
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-01-09
Filing date: 1956-01-09
Publication date: 1958-02-25
Anticipated expiration: 1975-02-25

Description

Feb. 25, 1958 G. w. GRISET 2,824,355

DEVICE FOR SETTING UP MOLDS FOR THE CONSTRUCTION OF CONCRETE STEPS Filed Jan. 9, 1956 INVENTQR. w srrser/ Guy K Fig.2

United States Patent F DEVICE FOR SETTING UP MOLDS FOR THE CONSTRUCTION OF CONCRETE STEPS Guy W. Griset, El Cerrito, Calif. Application January 9, 1956, Serial No. 557,915 2 Claims. (Cl. 255-118) The present invention relates to the construction of steps. More particularly the present invention relates to the molds or forms that are employed in the construction of concrete steps or stairs.

It is an object of the present invention to facilitate the task of setting up the mold or form for the construction of concrete steps or stairs.

' Another object of my invention is to provide a device by means of which a mold for the construction of concre'te steps may readily and quickly be set up by an ordinary workman.

More specifically it is an object of my invention to provide a device for holding the riser boards of molds, of the type referred to, in their proper and properly spaced positions relative to each other.

Still another object of my invention is to provide a device by means of which the riser boards of molds for the construction of concrete steps may be mounted in their proper positions in such a manner that the necessary pitch of the treads is automatically provided for.

An additional object of the invention is to provide a device, of the type referred to, that is easy to handle and which is of a simple and inexpensive construction.

Furthermore, it is an object of the invention to provide a device, of the type referred to, that may interchangeably be used at either end of the riser boards.

These and other objects of my invention will be apparent from the following description of the accompanying drawing which illustrates a preferred embodiment thereof and wherein Figure l is a fragmentary perspective, partly in section, of a mold for pouring concrete steps wherein the devices of my invention are employed; and

Figure 2 is a side elevation of one of the devices of my invention.

In Figure 1 the reference numeral indicates a slope along which concrete steps are to be constructed; For this purpose a pair of transversely spaced parallel side bars or

stringers

12a and 12b, preferably of wood, are held above theslope 1f; atan angle corresponding to the angle of ascent a (Figure 2) which the steps are to have, and at such an altitude'that the lower edges 14a and 14b of said bars lie above the outer edges 16 of thefsteps to be constructed. The

side bars

12a and 12b are rigidly held in the defined position in any conventional manner such as bymeans of stakes or poles (not shown) that aredriven into the ground at the opposite ends of said bars and which engage metal loops (likewise not shown) that are secured to the opposite ends of said bars. Supported from the

side bars

12a and 12b at equal intewals are transverse boards 18 that may likewise be of wood,

and which define the risers of the steps to be constructed and are therefore commonly known as the riser boards of the step mold.

To support the riser boards 18 at their opposite ends in their proper and appropriately spaced positions from the

side bars

12a and 12b, I employ pairs of transversely aligned brackets 20 that rest upon, and are secured to,

2,824,355 Patented Feb. 25, 1958 the upper edges 22a and 2250f the side bars 12a and 12!) respectively. Each of the brackets 26 is formed by a slender obliquely disposed bar of metal, such as steel, whose opposite ends are bent downwardly to form two straight

parallel legs

24 and 25 of equal length which are connected by a slanting center piece 26. The inner angle 5 (Figure 2) defined by the upper leg 24 and the center piece 26 and the outer angle 7 defined by the lower leg 25' and the theoretical downhill extension of said center piece 26 are both approximately complementary in size to the hereinbefore mentioned angle of ascent 0t at which the side bars 12a and 1212 are mounted and which is determined by the ratio of the intended height h of the risers 23 plus the vertical component 2 of the intended pitch of the treads 30 to the intended horizontal width w of the treads of the planned steps; and the perpendicular distance between the outer face 24a of the upper leg 24 and the inner face 25a of the lower leg 25 equals approximately the intended horizontal width of the treads. To secure the brackets 20 to the upper edges of the

side bars

12a and 12b,

cross pieces

32 and 34 are rigidly secured to the underside of the center piece 26 at points inwardly spaced from the inner faces of the

legs

24 and 25, respectively (Figure 2). These cross pieces project laterally at either side of the center piece 26 (Figure l) and both their projecting ends are provided with a pair of vertically extending holes 36 through which they may be nailed, as indicated at 37, to the upper edge of whatever side bar a particular bracket 20 has been placed upon. Due to the fact that the

cross pieces

32 and 34 project at either side of the center piece 26 and both their projecting ends are provided with holes 36, the same type of bracket 20 may be used on, and secured to either,

side bar

12a or 12b, as the case may be.

Both the

legs

24 and 25 of each bracket 20 are provided with a number of holes 38 that extend horizontally through said legs in a fore and aft direction at points, along their shanks, that are spaced from the underside of the center piece 26 by a distance which is larger than the width of the

side bars

12a and 12b. Through said holes 38 the ends of an upper and lower riser board 18 are nailed to the outer faces 24a of the upper legs 24 and the inner faces 25a of the lower legs 25 respectively of two transversely aligned brackets 20, as shown at 39 in Figure 2.

In practice a workman properly locates the highest riser board 18 for the steps to be constructed. As the next step, he places the side bars or stringers 12a and 1212 into approximately their proper positions over the uppermost riser board 18 with their bottom edges 14a and 14b respectively in contact with the upper outer edge 41 of said uppermost riser board. The workman then chooses a pair of brackets 20 whose angles {3 and 'y are about complementary to the angle of ascent a which the planned steps are to have, and which angle is determined by the ratio of the intended height h of the risers plus the vertical component p of the intended pitch of the treads, to the horizontal width w of the treads, as previously explained. Since these dimensions, are standardized in most communities for reasons of safety and the established standards are notfrequently departed from, the types of brackets 20 which a contractor may have to keep in store to satisfy what specifications he may encounter in his work, will not be many.

Continuing now with the practical application of the brackets 20 in setting up a step mold, the workman presses the outer face 24a of the upper leg 24 of a bracket of the proper conformation flat against the outer face 43 of the uppermost riser board 18 while the bracket rests with its

cross pieces

32 and 34 loosely upon the upper edge of the

respective side bar

12a or 12b, as the case may be, and as he holds the bracket in the described po- 3 sition, he shifts the

particular side bar

12a or 12b while leaving it in contact with the outer upper edge 41 of the uppermost riser board 18 until the side bar extends substantially parallel to the center piece 26 of the bracket with its upper edge 22a or 22b respectively in contact with the under surfaces of the

cross pieces

32 and 34. In this manner, both the

side bars

12a and 12b may be located at the proper angle. Thereafter, all the workman has to do is to secure them firmly at their opposite ends in any suitable manner to the ground. He then fastens the uppermost set of brackets 20 to the side bars 12a and 1211 by nailing the inwardly projecting ends of their

cross pieces

32 and 34 to the upper edges 22a and 22b respectively of said bars, while holding the outer faces 24a of the upper legs 24 of said brackets against the outer face 43 of the uppermost riser board whereupon he nails the upper legs 24 of said brackets to said uppermost riser board through the holes 38. Thereupon he nails the opposite ends of another riser board 18 of substantially identical dimensions to the inner faces 25a of the lower legs 25 of the two brackets 20 in such a position that the upper outer edge 41 of said board touches the lower edges 14a and 14b of the

side bars

12a and 12b respectively. This locates the second riser board (counted from the top) in its proper position with regard to the first riser board vertically as well as longitudinally of the steps, and due to the above described initial adjustment of the side bars 12a-and 12b against the highest set of brackets 20, it also provides automatically for the pitch which the tread to be formed between the inner bottom edge 44 of the uppermost riser board and the inner top edge 45 of the second riser board must have, to allow water to drain from the steps.

To find the proper place where the lower next pair of brackets 20 has to be secured t6 the

side bars

12a and 12b, the workman places another bracket 20 with the outer face 24:; of its upperlcg 24 against the last installed riser board 18 while resting the

cross pieces

32 and 34 upon a

side bar

12a or 12b as the case may be, as indicated in phantom lines at 42 in Figure 1. With said bracket in the described position, the inner face 25a of its lower leg 25 marks the transverse plane in which the outer faces 24a of the upper legs 24 of the next lower set of brackets 20 must lie for a riser board 18 nailed to said upper legs 24 to be situated in its proper place relative to the last installed riser board 18. The workman then nails the next set of brackets 20 through the holes 36 in the inwardly projecting ends of their

cross pieces

32 and 34 to the upper edges of the

side bars

12a and 12b, whereupon he is able to secure two consecutively lower riser boards 18 into their proper positions. In this manner the workman is able to complete the mold for the planned steps and to establish the proper pitch for the treads of the steps without need for special measuring instruments and without need for computations which the ordinary workman may find difiicult to perform. With the mold completed the concrete maybe poured into the space behind the riser boards and between appropriate side boards (not shown) in the customary manner to form the steps indicated at 46 in Figure 1. i 1 a When the concrete is being poured, the riser boardholding devices of the present invention are not in the Way of the workman and do not obstruct his field of operations, and after the steps have been poured and while the concrete is still in a state in which it may be worked upon, the

side bars

120 and 12b may readily be dismounted by extracting the ing the bars from underneath the nails 37 and withdrawbrackets 20, which latter remain in place and hold the riser boards in proper position relative to each other. At the end, the riser boards 18 may be lifted out with the aid of the brackets and the brackets 20 may be separated from the riser boards 18 by extracting the nails 39. With the step mold thus disassembled, everyone of its components including the brackets 20 may then be reused in the construction of other concrete steps.

While I have explained my invention with the aid of a particular embodiment thereof, it will be understood that the invention is not limited to the specific constructional details shown and described by way of example which may be departed from without departing from the scope and spirit of the invention. Thus, the

cross pieces

32 and 34 may be secured to the upper faces of the center bars 26 instead of to the lower faces thereof as illustrated. Also, while I have explained my invention in I connection with the construction of steps that have verti- -cal risers. the man skilled in the art, when acquainted with the principles of my invention, will readily devise brackets in accordance with my invention that may be employed in the construction of steps which have overhanging risers.

I claim:

1. In a mold for concrete steps including parallel transversely spaced side bars mounted to slant at the intended angle of ascent of the steps to be constructed, a device for suspending riser boards in appropriately spaced position from the side bars, said device comprising a center bar having two opposite ends, means on said center bar for securing it to one of said side bars in a position parallel thereto, a pair of parallel legs depending from the opposite ends of said center bar at an angle complementary to the angle of ascent of the steps, and means on both said legs for securing riser boards in parallel position to said legs.

2. In a mold for concrete steps including parallel trans versely spaced side bars mounted to slant at the intended angle of ascent of the steps to be constructed and having upper edges, a device for suspending riser boards in appropriately spaced position from the side bars, said device comprising a center bar having two opposite ends and two sides, cross pieces secured to said center bar and having opposite ends projecting at either side of the center bar, means on the oppositely projecting ends of said cross pieces for securing the center bar to the upper edge of one of said side bars, in a position parallel thereto, a pair of parallel legs depending from the opposite ends of said center bar at an angle complementary to the angle of ascent of the steps and at a perpendicular distance fromeach other substantially equal to the horizontal width of the tread of said steps, and means on both said legs for securing riser boards in parallel position to said legs.

References Cited in the file of this patent UNITED STATES PATENTS I Brewer Oct. 6,